26. ACIPENSERIDiE — ACIPENSER. 
87 
hooked spine. Skin A ery rough. Snout about as in A. transmontams^ 
sharj) in the young, becoming blunt with age, usuallj" rather sliortei 
than the rest of head. Barbels nearly midway between snout and 
mouth. Gill-rakers scarcely higher than broad, about 17 in number. 
Upper lobe of tail with some scattered plates. Caudal fulcra not en- 
larged. Lower lobe of caudal short and blunt, little more than half the 
length of the npimr. Dorsal plates 10 ; lateral 28-30 ; A^entral 9. Anal 
fin about half below the dorsal. D. 37; A. 30. Depth 7-| in length; 
head 1|. Pacific coast, ascending the rivers from San Francisco north- 
ward, reaching a large size. Less abundant than A. transmontanus; 
not used for food, being reputed iioisonous. 
(Ayres, Proc. Cal. Acad. Nat. Sci. i, 15; GUntlier, viii, 342: Acipenser agassizi Guuther, 
viil, 344 : Acipenser acutirostris GUntlier, viii, 344; not of Ayres.) 
77 . A. Le Suenr. — Lake Sturgeon; Ohio Sturgeon; Black Sturgeon; 
Stone Sturgeon ; Bock Sturgeon. 
Blackish above, sides iialer or reddish. Body comparatively elongate ; 
snout slender and long in the young, becoming quite blunt with age, 
when it is considerablj’ shorter than the rest of the head; shields large, 
rough with strongly hooked spines, becoming later comparatively 
smooth. Skin with minute rough plates. Ventral shields growing 
smaller with age, and finally deciduous. Dorsal shields 13 (11-lG); 
lateral shields (34) 30-39; ventral i)lates 8-10. D. 35; A. 26. L. 6 
feet. Weight 50 to 100 pounds. Mississippi Valley, Great Lakes, and 
northward. Our common fresh- water sturgeon, usually not descending 
to the sea. 
(Le Sueur, Trans. Amer. Phil. Soc. i, 1818,388: Acipenser maculosus Le Sueur, Traus. 
Amer. Phil. Soc. i, 393: Acipenser rupertianns Richardson, Fauna Bor. -Amer. iii, 311: 
Acipensei' carbonarius, Iwvis, and rhgnchccus Agassiz, Lake Superior, 271, 276: Acipenser 
ruhieundus, maculosus, and liopeltis Guuther, viii, 333, 339, 341 ; Milner, Rei)t. U. S. Fish 
Com. 1872-73,67.) 
78. A. brcvirosli’is Le Sueur. — Short-nosed Sturgeon. 
“ Snout very short and obtuse, about one-fourth of the length of the 
head. Barbels short, simple. Osseous shields rather small and distant 
from one another, finely radiated and granulated ; 8-10 on the back, 
22-28 on the sides, G-8 along the abdomen. Skin y^ery sparingly cov- 
ered with minute prickles and very small scattered ossifications. The 
greater part of the anal below the dorsal. D. 30.” {GUntlier.) Cape 
Cod to Florida. 
(Le Sueur, Trans. Amer. Phil. Soc. i, 390; Gunther, viii, 341.) 
